February 18 – Making Sparks

Today’s Factismal: The first modern battery was built in order to investigate frog’s legs.

Today is Alexandra Volta’s 270th birthday. In lieu of the normally-scheduled factismal (on noise pollution), I’ve substituted a rerun of another factimsal about Volta’s creation of the modern battery. Enjoy!

If you’ve studied the history of science, then you know that nothing drives the discovery of new things like an argument between two scientists. Cope fought with Marsh and the result was an (almost literal) explosion of new dinosaur discoveries (including some that weren’t). Hawking fought with Presskill and the result was a deeper understanding of how black holes work (and a new encyclopedia for Presskill). Newton fought with Leibnitz and the result was a new type of math that would describe the universe and plague college freshmen forever after. And, around 1780, Galvani fought with Volta and the result was the discovery of how nerves work and how to create electricity.

As with most feuds, it started over something small but interesting. While Galvani was working with frog’s legs, trying to tease out the secret of the nerves, his assistant touched a frog’s leg with a scalpel – and it twitched! If your pork chop dinner jumped up and did the tango, you wouldn’t have been half as astonished as the two scientists were. They quickly tried an assortment of things to replicate the result and discovered that it only worked when the metal scalpel touched the frog’s leg; feathers, wooden sticks, and quill pens had no effect. Galvani declared that he had discovered “animal electricity” and sent the details out to the world.

Volta, who was a sometime colleague of Galvani’s, wasn’t convinced. He replicated the experiment and was able to make twitching frog’s legs of his own, but he didn’t think that the secret was in the animal; he thought that it was in the scalpel. If the electricity were in the animal (as Galvani supposed), then just about anything would have made it twitch. But if the electricity were being created by the metals, then only being touched by a metal thing would make it twitch. And in a series of experiments stretching over several months, that’s exactly what Volta proved: it was the two metals that made the electricity.

Look, ma! I made a battery!

Look, Ma! I made a battery!

But then Volta went one step further and made the world’s first modern wet cell battery. He kept the two metals but substituted paper soaked in salt water for the frog’s legs (the paper stacked better than frogs legs do). By alternating layers of metal and slipping paper between the metal, Volta was able to generate a steady electric current. The modern lead-acid battery (found in most cars) was born.

If you’d like to build a “Voltaic pile” of your own, all you’ll need is five nickels, five pennies, some paper towels, a plate, and a bowl of salt water. First cut small circles out of the paper, just slightly smaller than a penny. Next, put a nickel down on the plate. Dip a paper circle into the salt water and then place it on top of the nickel. Top it with a penny, then dip another paper circle into the salt water and put it on top of the penny. Continue stacking the coins and paper until you’ve got a tower ten coins high. Your battery is now done! To see if it is working, you can try connecting it to a LED or ammeter with a pair of wires or simply touch the ends of the wires to your tongue; the bitter taste you get is caused by the flow of electricity across your tongue.

And the coolest thing about making that Voltaic pile is that it means you’ve made something sciency. For more science making ideas, go to:

February 16 – Blinding A Bat

Today’s factismal: Some moths have long tails that “jam” bat’s sonar.

Ask any biologist and she will tell you that all of life is in an arms race. Things that eat are constantly developing new and better ways to nibble on tasty things and things that don’t want to get eaten are constantly trying to find new and better ways of avoiding the dinner invitation. And perhaps no better example of this exists than the world of moths and butterflies because these lovely lepidoptera (“scaly wings”) are both eaters and eatees.

This butterfly's tongue helps it get fed without getting bogged down (My camera)

This butterfly’s tongue helps it get fed without getting bogged down
(My camera)

We all know about the Monarch butterfly and its ingenious use of the milkweed plant. By nibbling on milkweed leaves as a caterpillar, Monarchs make themselves inedible as adults and advertise that fact with their bright red and black coloring. But they are hardly the only example in the fluttering world. Consider the tongue of most butterflies and moths. So long that it can’t even fit back in their mouth, the tongue is a hollow, flexible drinking straw. They’ve developed these over-sized tonsil ticklers not because they want to give the world’s biggest Bronx cheer but because they were fighting with plants. You see, many butterflies and moths get their food as adults from the nectar hidden in plant flowers. The plants put out the nectar to attract these critters with the hope that some of the plant pollen will get carried to the next flower where it will start the next generation of flora. But pollen is heavy for a critter as small as a butterfly, so they developed long tongues to allow them to sip from the flower without getting near the pollen. The plants respond by growing longer flowers and before you know it you’ve got the butterfly tongue we know and laugh at.

The long tails of these moths may jam bat sonar (My camera)

The long tails of these moths may jam bat sonar
(My camera)

And lepidoptera don’t just nibble on things. They also get nibbled on. Some, like the Monarch, adapt by eating poisonous plants. Other adapt by flying at night when there are fewer critters out there eating little fluttering things. But that’s when bats feed and bats like butterflies and moths just fine, thank you very much. So some moths have adapted to the attack of bats by developing long tails. These tails flutter as the moth flies in the night, which then scatters the bat’s sonar; instead of hearing a sharp “ping!” indicating where the moth is, they hear a fuzzy “pong” that gives them less of an idea where the bug might be flying.

If you’d like to learn more about the butterflies and moths of the world and maybe help with a citizen science project that aims to get a picture of every single one, then why not flit over to Butterflies and Moths of North America?


February 15 – Staying Sane

Today’s factismal: Staying active with lots of hobbies has been shown to stave off dementia in older people.

One of the miracles of the modern age is that more people are living longer. A lot longer. For example, the oldest person in the world today is Misao Okawa of Japan, who was born on March 5, 1898, making her more than 116 years old! And today there are more “supercentenarians” than ever. And that i causing both rejoicing and trouble.

The trouble comes about because not every part of us makes it past 100; livers wear out, knees give way, hearts get iffy. But the most serious trouble is with the brain, the very thing that defines us as a people. As some people get older, their brain begins to malfunction; they can no longer remember their friends and family, or they have problems with simple tasks such as getting dressed. The medical term for this is dementia.

Though we don’t have a cure for dementia (yet), doctors have noticed that those who don’t get it have some habits in common. And one of the most important habits for staving off dementia turns out to be having lots of friends and lots of hobbies. Doctors think that the social interaction of having lots of friends helps keep the brain in shape and the habits of hobbies help the brain remember other rote tasks.

Some of Alfred Date's sweater for penguins (Image courtesy PINP/AAT Kings/Spotlight/Rex USA)

Some of Alfred Date’s sweater for penguins
(Image courtesy PINP/AAT Kings/Spotlight/Rex USA)

Perhaps the best example of this is Alfred Date, who is Australia’s oldest man at 109 years old. He has an extensive social life and many hobbies, including knitting sweaters for penguins. The sweaters come in handy when the penguins are accidentally covered with oil; the sweater keeps them from preening and swallowing the oil. And Alfred’s hobbies keep him mentally sharp and ready for anything.

Now, if you are looking for a hobby to keep you mentally fit, why not join a citizen science project? Something like AgeGuess would help keep you going well into your ripe old age! AgeGuess is a project that seeks to understand the visible signs of aging by having volunteers submit their photo for people to guess their age and by having volunteers guess the age of others. To participate, head over to:

February 14 – The Two Percent Solution

Another Saturday, another adventure! Today, Peter and Mary discover how a little change can make a big difference.


One day at school, Mary was sitting at the lunch table staring worriedly into a bottle of soda as Peter walked by with his tray.

“What’s the matter?” he asked.

“My dad said that we’re making too much carbon dioxide,” Mary replied. “But I don’t see how something that makes the bubbles in my soda can be harmful.”

“It is also in our breath,” reminded Peter. “And it comes out of smokestacks and tailpipes. But my dad says that it only makes up a small part of the atmosphere. So how could it matter?”

“You’ll find out when you come to class today!” said Mr. Medes as he walked by. Not only was Mr. Medes their favorite teacher, his classes often included experiments. Since they both wanted to be scientists, this gave them a chance to learn what they would do when they grew up.

Eagerly, the two finished their lunch and went to the science lab. Sitting on each lab table were three one-liter bottles, three aquarium thermometers, a teaspoon, and a small bottle of food coloring. Once the class had settled down, Mr. Medes starting explaining the day’s experiment.

“Today, we are going to make a model of the atmosphere,” he said. “Who knows what a model is?”

“It is something that scientists use to help them understand how a natural event that is too big to see in the lab works,” said Mary.

“That’s right,” Mr. Medes replied. “And models allow us to change just one thing and see how that makes the entire system change. It is always easier to change a model than to change the world, and it is certainly a lot easier to clean up!”

“What are we going to change?” asked Peter.

“We are going to see what effect increasing carbon dioxide has on the atmosphere,” said Mr. Medes. “To do that, we’ll use water to represent the atmosphere and red food coloring to represent the carbon dioxide. You’ll put the same amount of water in each of the three bottles and tape an aquarium thermometer to the outside of the bottle.”

“Why a thermometer?” asked one of the students.

“Because some scientists think that changing the amount of carbon dioxide in the atmosphere will change the temperature of the atmosphere,” Mr. Medes replied. “We’ll add one teaspoon of red food coloring to one bottle of water, two teaspoons to another, and we’ll leave the third bottle alone. Then we’ll put the caps on the bottles and put them onto the windowsill where they can get some sun. What do you think will happen?”

“The water will turn red in the bottles with the food coloring!” said Mary.

“Anything else?”

“The bottles will get warm from the sun,” said Peter. “All three will get warmer.”

“But the one with the most food coloring won’t get any warmer than the others,” Mary added.

“OK, you’ve made your predictions,” said Mr. Medes. “It’s time to do the science!”

What do you think will happen? Do the experiment!




The students carefully filled the bottles at the water tap, then taped on the thermometers. They added a teaspoon of red food coloring to one bottle and two teaspoons to the second.

“Hey! This one is a lot darker than the one with just one teaspoon of food coloring!” Peter said.

“OK,” said Mr. Medes. “That’s our first observation: More food coloring makes the water darker. Now put the caps on and put the bottles on the window sill.”

While the students followed his instructions, he wrote “More food coloring = darker” on the board at the front of the class.

“We can’t see carbon dioxide,” Mr. Medes said as he turned back to the class. “But that doesn’t mean that light can’t see it. If you remember our experiment with rainbows, you know that there are many different colors of light. But the colors of light that we can see aren’t the only colors. There are lots of colors that we can’t see. One of these colors is called infrared because it lies just below red. And it just so happens that carbon dioxide is exactly the right color to catch infrared. So carbon dioxide makes infrared stay a little longer in the atmosphere.”

“Why is that important?” asked Peter.

“We’ll see at the end of class. In the meantime, let’s go over the rainbow experiment again,” replied Mr. Medes. For the next thirty minutes, he led them through the exercises about the colors of light. Near the end of class, he said “OK, now everyone go look at the thermometers on your bottles of water.”

“Hey!” said Mary. “The bottle with more red food coloring is almost two degrees hotter than the one with just a little!”

“And they are both warmer than the one with no red food coloring!” Peter added.

“That’s right,” said Mr. Medes. “The extra red food coloring caught more of the sun’s energy and kept it in the bottle just a little longer. That made the bottle warmer than the one with just a little food coloring and much warmer than the bottle with no food coloring.”

“So more carbon dioxide means that the light stays around longer and the Earth gets warmer?” asked Mary.

“Yes, that’s right. Without carbon dioxide, the Earth would be a frozen ice ball. But, because the amount of carbon dioxide has been going up, the Earth’s atmosphere has been getting warmer.”

“I like it warm!” said one of the students.

“So do I,” said Mr. Medes. “But more heat means more droughts and other problems. Carbon dioxide also helps plants grow, but that’s one of the few good things that we can expect. We could reduce the amount of carbon dioxide we make, but even if we do we’ll still have problems for the next century from the stuff we’ve already put into the atmosphere. As with most interesting problems, there are no easy answers.”

And with that, the bell rang and everyone left for the next class.

February 11 – Beware of DHMO!

Today’s factismal: The average vaccine includes about eight ingredients.

If you are ever looking for something to scare the pants off of someone, point out the many dangers of dihydrogen monoxide. If you believe the hype, it is one of the most dangerous chemicals around and kills at least ten people each day. But if you know the science then you know that dihydrogen monoxide is just another way of saying “water” and that its benefits far outweigh the risks.

The same is true of vaccines. If you look at the CDC’s list of ingredients in vaccines and don’t know the chemistry and biology, then it can be pretty scary. There are about 200 ingredients given for the 53 vaccines listed and many of them have names like D-fructose and phenol. But once you know what the ingredients are for (and what levels there are of them), then you realize that the folks telling you that vaccines have “poison” in them are about as truthful as the folks who claim that dihydrogen monoxide is a deadly killer.

The number of ingredients in vaccines (Data courtesy CDC)

The number of ingredients in vaccines
(Data courtesy CDC)

In general, the ingredients in a vaccine are there for one of five reasons: they cause your immune system to develop an immunity, they stimulate your immune system, they feed or nurture the stuff in the vaccine, they keep other viruses and bacteria from growing in the vaccine, or they make the vaccine easier to use. Let’s look at each of these categories in turn.

First, the stuff that causes your immune system to develop an immunity; when listed, it is given names like MRC-5 cellular proteins or insect cell, bacterial, and viral protein. Generally, this is the virus itself usually present in a weakened form (“live vaccines”) or as a protein fragment (“killed vaccines”). When exposed to these viruses in a controlled way, your immune system develops a specific set of antibodies that will attack that virus the next time it is seen. This the basis of Jenner’s vaccinations against smallpox back in 1796. Indeed, that’s what gave us the word “vaccinate”; because Jenner used cowpox to prevent smallpox, the word for the procedure was “born from a cow” or “vacca (cow) innatus (born in)”. Without these bits of the virus, the vaccine would be nothing but a shot of water with trace bits of other stuff.

Next, there’s the stuff to stimulate your immune system. Basically, this stuff is the equivalent of trash-talking before a big fight. Known in medical circles as an adjuvant (“helper”), these chemicals and compounds help make your immune system more sensitive to the active ingredient. So what is in here? Aluminum hydroxide – also known as Gaviscon to you folks with upset stomachs. Dibasic sodium phosphate – which is also used as a leavening agent for bread at the store. And aluminum potassium sulfate – also known as alum or “that stuff that makes pickles so darn sour”.

Third is the stuff that helps the viruses used in the vaccine grow. Most vaccines are grown in what medicos call prosaically enough a “growth medium”. Typical things used for a growth medium include gelatin (just like in Jell-O), agar (just like in toothpaste), and eggs (just like in your breakfast). Basically, if the ingredient name includes “medium”, then it was used to grow the stuff. Though most of this is removed before use, trace amounts always remain. Under US law, those growth media that might cause allergic reactions (such as eggs) or religious problems (such as beef) must be labeled and identified to the patient before use.

Vaccines contain trivial amounts of antiseptics (Data courtesy CDC)

Vaccines contain trivial amounts of antiseptics
(Data courtesy CDC)

Fourth, we’ve got the stuff to keep other viruses and bacteria from growing in the vaccine. The reason for this is obvious; what allows one virus to grow also allows other viruses to grow, along with bacteria and assorted other things that we don’t want. So it is common practice to include antiseptics in the vaccine growth medium and in the vaccine doses to keep them sterile. The most common antiseptic used is formaldehyde, which is found in 28 of the 53 vaccines in the list. Formaldehyde is used because it is very effective as an antiseptic in small doses; typically, there is about 100 micrograms of formaldehyde in a dose of vaccine. For comparison, a typical human has about 6,000 migrograms of naturally-occurring formaldehyde in their blood. Similarly, some vaccines have neomycin (the same stuff found in Neomycin) and a very few have thimerosal (the same stuff found in Merthiolate and many tattoo inks). That last is somewhat controversial due to a now-discredited study (it turns out the guy made up his data {and abused his young patients} so he could make some money) but removing it has increased the costs of vaccines to the point where they are now unaffordable in many third-world countries. As a result, death rates in those countries have increased.

Finally, there is the stuff to make the vaccine easier to use. Most of this is chemicals that keep the bits of dead virus from sticking to each other and forming clumps or that make the vaccine easier to inject. They include potassium chloride (also known as “salt-free table salt”) and potassium phosphate (also known as “the anti-caking agent in soft drink mixes”) and citric acid (also known as “orange juice”) which help to keep the vaccine in the proper pH range and mineral salts (also known as Epsom salts) which help give it the proper salinity. And, of course, every dose of vaccine also has a large dose of dihydrogen monoxide; it is what everything is suspended in.

So that’s what is in a vaccine. A lot of scary sounding stuff that, like dihydrogen monoxide, turns out to be pretty banal once you know what it is and where you’ve seen it before.

February 10 – Walking On Air

Today’s factismal: The US government has begun a $3.2 million program to help save the Monarch Butterfly!

Today there is good news out of Washington, DC! The US Fish and Wildlife Service has begun a $3,200,000 program to help save the Monarch Butterfly. Before we get into the details of the program, let’s get the obvious out of the way: yes, this is needed. Every year, hundreds of thousands of Monarch butterflies fly from where they were born to a place they have never seen in order to lay their eggs. Even better, Monarchs can act as an early warning system of environmental changes. And, of course, it is just plain pretty. But lately there’s been something wrong with the Monarch butterfly ; where there used to be billions of them winging their way each year, now we have just a few hundred thousand. We don’t know why the population has declined and if it is permanent. Is it climate change? Is it changes in land use? Is it due to parasites? Is it a natural fluctuation? We simply don’t have enough information to decide.

Monarch population over the years [Data from Monarch Butterfly Biosphere Reserve (MBBR) of the National Commission of Natural Protected Areas (CONAP)]

Monarch population over the years
[Data from Monarch Butterfly Biosphere Reserve (MBBR) of the National Commission of Natural Protected Areas (CONAP)]

But given the strong decline in the number of Monarchs, the US Fish and Wildlife Service has taken the first step in helping to preserve the species. They’ll spend some $2 million on restoring habitat for the Monarch by planting milkweed and other native plants in more than 200,000 acres spread from California to Iowa to Ohio to Arkansas to Texas; everywhere that Monarchs fly will see an upgrade. They’ll also work with more than 750 schools to plant butterfly gardens to be used by the butterflies as a spot to rest, to east, and to lay their eggs and by the teachers and students as a place to observe the wonders of nature close-up. The rest of the money will create a conservation fund to encourage farmers and landowners to preserve natural habitats.

A Monarch after a rain shower  (Image courtesy Journey North)

Will the Monarch soon be no more? (Image courtesy Journey North)

If you don’t want to wait for the government to solve the problem, why not plant some milkweed for the Monarchs in your neighborhood to feast on? Despite the name, milkweeds are beautiful and colorful plants that can brighten up any garden. To order seeds, head to your nearest nursery or flit your browser to:

February 9 – Puttin’ On The Blitz

Today’s factismal: At the first bioblitz, citizen scientists identified 974 species in under 24 hours; that’s one species every ninety seconds!

One of the more interesting things about becoming a citizen science is how it changes the way that you view the world around you. You may suddenly start noticing patterns in the weather, or see beauty in the night sky that you hadn’t seen before. Or, if you take part in a bioblitz (an intense, day-long effort to identify every species in an area), you may realize just how many different species we share our world with – even in an urban environment.

The first bioblitz was held nearly 18 years ago in Kenilworth Park and Aquatic Gardens, located in Washington, DC. The citizen science volunteers were people just like you who decided to spend a couple of hours looking at the plants and animals in the park and trying to build a catalog of them. And in the 24 hours that it took to complete the bioblitz, they discovered 974 different species, including one lonely little protozoan, 650 types of insect, 150 types of plants, 76 types of birds, and nine types of mammals (not counting people). By cataloging all of these different species, they were able to get a better understanding of how the local ecosystem works. And, by repeating the bioblitz each year, they’ve been able to track how that ecosystem is changing and to determine what (if anything) they need to do about it.

If this sounds like fun to you, then why not participate in a bioblitz near you? And if there isn’t one near you, then why not work with your local park department or college to do a bioblitz? (Teachers: This also makes a great educational opportunity!) To learn more, head over to National Geographic’s FieldScope which will give you the tools you need to put on your very own bioblitz: